Control system



Feb. 27, 1934. w. 1. BENDZ 1,948,694

CONTROL SYSTEM Filed July 30. 1961 mi l-mul INVENTOR WITNESSES:

' Waldemar I Benn z RMMM ATTOR'NEY determined zone.

Patented Feb. 27, 1934 UNITED STATES w en:

PA ENT orrica CONTROL SYSTEM Application July 30, 1931. Serial No.554,135 Claims. (Cl.246--130) My invention relates, in general, tocontrol systems and more particularly to systems for controlling theoperation of railway grade-crossing gates.

An object of my invention, generally stated, is to provide a controlsystem for railway-crossing gates which shall be safe and reliable inoperation and which may be readily and economically manufactured andinstalled.

A more specific object of my invention is to provided for automaticallyraising and lower- *ing a railway-crossing gate as a train passes thecrossing.

Another object of my invention is to provide "an automatic controlsystem for a railwaycrossing gate which will permit the gate to bemanually controlled, under predetermined conditiona Other objects of myinvention will be described fully hereinafter or will be apparent tothose skilled in the art.

According to my invention, railway-crossing gates are automaticallycontrolled by relays which are actuated when a train enters a pre-Manual control switches are provided which permit a brakeman, or otherauthorized person, to raise the gates while a trainis standing on thecrossing. However, if a train approaches the crossing on another track,the gates are automatically lowered. Provision is made for automaticallyrestoring the equipment from manual to automatic control after apredetermined interval of time, thereby preventing any person iromleaving the crossing unprotected by the automatic control system. For afuller understanding of the nature and scope of my invention, referencemay be had to the following detailed description, taken in conjunctionwith the accompanying drawing, the single figure of which is adiagrammatic view of a control system organized in accordance with myinvention.

Referring to the drawing, 10 designates a railway-crossing gate that isdisposed to guard a railway crossing 11 when a train is passing oneither of the tracks 1 or 2. In order to simplify the drawing anddescription, only one gate is illustrated. However, it will be readilyunderstood that as many .gates as desired may be controlled by theautomatic control system herein described. It will also be apparent thatthe system may be expanded to provide for any number of tracks by addingadditional equipment similar to that illustrated.

As illustrated, the gate 10 may be raised and transformer 32 and arectifier 33.

lowered by means of a hydraulically-operated piston 12 that is disposedin a cylinder 13. The

piston 12 is actuated by a reversible pump" 14,

which is disposed to force the actuating fluid from one cylinder gate10.

The pump 14 may be driven by either of two motors 15 or 16, which areconnected to a 13, thereby raising and lowering the drive shaft 1'7. Themotors 15 and 16 are both of In order that the operating motor may bestopped when the gate 10 has reached either its upper or lower limit oftravel, limit switches 23 and 24 are provided. The limitswitchesarenormally biased to their closed positions by suitable springs and.are sodisposed that the switch 23 is actuated to its open position whenthe gate 10 is raised to its uppermost position, and the switch 2a isopened whenthegate 10 is lowered. The limit switches 23 and 24arealso-utilized to control a warning bell 25 and relays 26 and 27, whichcontrol signal lamps 28, located on the gate indicate when the gate 10is closed.

The motor 15 and the control equipment are normally operated byalternating current supplied through conductors L1 and L2, which may beconnected to an alternating-current source of power (not shown). In casethe alternating;- current power, fails, the gate 10 is operated by thedirect-current motor 16. A storage battery 29 is provided for operatingthe motor 16 and the control equipment in case the alternating-currentsource of power fails. r

Atransfer relay3l is so connected in the control system that the controlapparatus and the motor connections are automatically transferred fromthe alternating-current source to the directcurrent source when thealternating-current source fails. The storage battery 29 is maintainedin a charged condition by means of a In order that the gate 10 may beautomatically lowered when a train approaches the crossing 11 and beautomatically raised after the train has passed the crossing, trackrelays 34 and 35 are connected to insulated sections of the tracks 1 and2, respectively. The energy for operating the side of the piston to theother in the 7' arm, to

track relays 34 and 35 is supplied by storage batteries 36 and 37,respectively. The operation of the track relays will be described morefully hereinafter.

The track relays 34 and 35 control a plurality of reversing switches 38,39, 40 and 41, which, in turn, control the operation of the motors 15and 16. The switches 38 and 39 control the directcurrent motor 16, andthe switches 40 and 41 control the alternating-current motor 15.

Each of the motors 15 and 16 is protected against an excessive currentby an overload relay, the actuating coil of which is connected in thecorresponding motor circuit. The alternating-current motor 15 isprotected by the overload relay 42, and the direct-current motor 16 bythe relay 43. The relay 42 is so connected in the control system thatthe transfer relay 31 is actuated to transfer the control apparatus fromthe alternating-current source to the direct-current source in case ofan overload on the alternatingcurrent motor 15. The gate 10 will,therefore, continue to be operated by the direct-current motor 16 in theevent of an overload or a short circuit on the alternating-currentmotor.

In order that the gate 10 may be operated by a brakeman, or otherauthorized person, while a train is standing on either of the tracks 1or 2, manual control switches 44, 45 and 46 are provided fortransferring the control equipment from automatic to manual control. Thecontrol equipment may be set for manual control for a predetermined timeinterval, after which it will be transferred to automatic control by atiming relay 47, thereby leaving the crossing unprotected by theautomatic equipment.

The timing relay 47 is so constructed that the period of time, duringwhich the gate 10 may be controlled manually, may be varied. In case itis desired to maintain manual control for an interval of time greaterthan the time setting of the relay 47, the relay may be reset by apush-button switch 48. Two auxiliary relays 49 and 51 cooperate with thetiming relay 47 to limit the interval of time during which the gate 10may be manually controlled.

In order that the functioning of the apparatus may be more clearlyunderstood, the operation of the control system will now be described.Assuming that the apparatus is actuated 130213118 respective positionsshown on the drawing and that the conductors L1 and L2 are connected toan alter hating-current source of power, the actuating coil of thetransfer relay 31 will be energized to actuate the relay to itsuppermost position to connect the conductor 52 to the conductor L2 andthe conductor 53 to the conductor L1. The control apparatus is,therefore, operated by alternating current.

As previously explained, in case the alternating-current source fails,the actuating coil of the relay 31 is deenergized, and the relay dropsto its lowermost position to connect the conductor 52 to the negativeterminal of the battery 29 and the conductor 53 to the positive terminalof the battery, thereby providing a direct-current source of energy foroperating the control apparatus.

It will be observed that the actuating coils of the track relays 34 and35 are connected across the terminals of the batteries 36 and 37,respectively. Therefore, the relays 34 and 35 are actuated to theiruppermost positions, as shown on the drawing.

preventing any person from position, the

Assuming that a train enters the insulated section of track 1, a shuntcircuit is established around the actuating coil of the track relay 34by the wheels and axle of the locomotive, which permits the relay 34 todrop to its lowermost position. The shunt circuit may be traced from thepositive terminal of the battery 36, through conductor 54, the rails oftrack 1, which are bridged by the locomotive, conductor 55, the switch44 and the resistor 56, to the negative terminal of the battery 36.

When the relay 34 is permitted to drop to its lowermost position, theactuating coil of the switch 40 is energized, thereby closing the switch40, which causes the motor 15 to be operated in a direction to lower thegate 10. The circuit for the actuating coil of the switch 40 may betraced from the energized conductor 52, through contact members 57 and58 bridged by the contact segment 59- conductor 61, the actuating coilof the switch 40, conductor 62, the contact members 63 and 64-bridged bythe contact segment 65-and conductor 66, to the conductor L1.

When the switch 40 is closed, the motor 15 is energized through acircuit which extends from the energized conductor 53, through thearmature of the motor 15, the field winding 19, conductor 67, contactmembers 68 and 69-bridged by the contact segment 71-conductor 72, theactuating coil of the overload relay 42 and conductor 73, to theenergized conductor 52. The pump 14 is driven by the motor 15 in adirection to cause the piston 12 to be actuated in the cylinder 13 tolower the gate 10.

When the switch 40 is closed, a circuit is also established whichenergizes the bell 25 to give a warning that the gate 10 is beinglowered. This circuit may be traced from the positive terminal of thebattery 29, through conductors 74 and 75, contact members 76 and77bridged by contact segment 78conductors '79 and 81, the bell 25 andconductors 82, 83 and 84, to the negative terminal of the battery.

When the gate 10 is actuated to its lowermost interrupting the circuitthrough the actuating coil of the switch 40, which permits the switch toopen to interrupt the circuits for the motor 15 and the bell 25.

As soon as the motor 15 starts to lower the gate 10, the contact membersof the limit switch 23 are permitted to close, thereby energizing theactuating coil of the switch 26 to connect the lamps 28 to thealternating-current source. The circuit through the actuating coil ofthe switch 26 may be traced from conductor L1, through conductor 85, thecontact members 86 and 87-bridged by the contact segment 88conductor 89,the actuating coil of the switch 26, conductor 91, contact members 92and 93-bridged by the contact segment 94 of the switch 27-and conductor95, to the energized conductor 52. It will be seen, that the lamps 28will be lighted as soon as the gate 10 starts to lower and remainlighted until the gate is returned to the raised position. The circuitthrough the lamps may be traced from a terminal 171 of the transformer32 through conductor 172, contact member 173 of the switch 26,conductors 174 and 175, the lamps 28, conductors 176 and 177, contactmember 178 and conductor 179 to the terminal 180 of the transformer 32.

When the train has passed over the crossing 11 and has entirely clearedthe insulated section of the track 1, the shunt circuit around theactuating coil of the relay 34 is interrupted, thereby 1 permitting thecoil of the relay 34 to become energized. When the relay 34 isenergized, circuits are established which cause the gate 10 to beraised, provided a train is not approaching on the track 2. When therelays 34 and 35 are both actuated to their uppermost positions, theactuating coil of the switch 41 is energized, thereby closing it tocause the motor 15 to rotate in a direction to raise the gate 10. Thecircuit for the coil or" the relay 41 may be traced from the energizedconductor 52, through conductor 96, contact members 97 and 98-bridged bythe contact segment 99-conductor 101, contact members 102 and103-bridged by the contact segment 104- conductor 105, the actuatingcoil of relay 41, conductors 106 and 89, contact segment 88 of the limitswitch 23 and conductor 85, to the conductor L1.

, When the switch 41 closes, an energizing circuit is established forthe motor 15, causing it to rotate in a direction to raise the gate 10.The

motor circuit extends from the energized conductor 53, through thearmature of the motor 15,

the field winding 13, conductor 107, the contact members of switch 41,conductors 108 and '72, the actuating coil of the relay 42 and conductor73, to the energized conductor 52. When the gate 10 is raised to itsuppermost position, the motor 15 is stopped by the limit switch 23,which is opened to interrupt the circuit through the actuating coil ofthe switch 41.

As previously explained, in case the alternatingcurrent conductors L1andLz become deenergized, or the relay 42 is actuated because of anoverload, the circuit through the actuating coil of the relay 31-whichextends from conductor L1, through conductor 109, the actuating coil ofthe relay 31, conductor 111, the contact members of the relay 42 andconductor 112 to conductor L2- is interrupted, thereby permitting therelay 31 to drop to its lowermost position to connect the battery 29 tothe conductors 52 and 53 to supply energy for operating the controlapparatus. In the event that a train enters the insulated sections ofthe tracks while the control apparatus is being operated by the battery29, the switches 38 and 39 are energized to control the motor 16.

As previously explained, the track relay 34 is permitted to drop to itslowermost position when a train is on track ll If a train approaches ontrack 1 while the control apparatus is being energized from the battery29, the switch 38 is actuated to connect the motor 16 to the conductors52 and 53, which are energized by'the battery 29. The circuit throughthe actuating coil of the switch 38 may be traced from the energizedconductor 83, through conductor 113, the contact members of the relay43, conductor 114, contact members 115 and INS-bridged by the contactsegment 11'7conductors 118 and 119, the coil of the switch 38, conductor121, contact members 122 and 123-bridged by the contact segment 124- andconductor 125, to the energized conductor 53.

When the switch 38 is closed, the motor 16 is connected to the powersource to drive the pump 14 in a direction to lower the gate 10. Thecircuit through the motor 16 may be traced from the energized conductor53, through the armature of the motor 16, the field winding 22,conductor 126, the contact members 127 and 128-bridged by the contactsegment 129conductor 131, the actuating coil of the overload relay 43and conductor 132. to the energized conductor 52.

When the switch 38 is closed, a circuit is also established for the bell25, through the contact segment 133-bridged by the contact members 134and 135-thereby causing the bell 25 to be rung while the gate is beinglowered, as previously explained.

The lamps 28 are connected to the battery 29' by means of the relay 27,which is actuated to its uppermost position as soon as the gate 10starts to lower. The circuit for the actuating coil of the relay 27 maybe traced from the energized conductor 53, through conductor 136,contact members 137 and 138bridged by the contact segment 139-conductor141, contact members 142 and 143bridged by the contact segment144conductor 145, the coil of the relay 27 and conductor 146, to thenegative conductor 83. The lamps 28 are, therefore, connected to thebattery 29 in place of to the transformer 32, as they were while thecontrol apparatus was being operated by alternating current.

When the gate 10 is in its lowermost position, the motor 16 is stoppedby the limit switch 24,

which is opened to interrupt the circuit through the actuating coil ofthe switch 38.

When the train has passed the crossing, the actuating coil of the relay34 is again energized, as previously explained, and the switch 39 isclosed to cause the motor 16 to drive the pump 14 in a direction toraise the gate 10. The circuit for the coil of the switch 39 extendsfrom the previously energized conductor 114, through conductor 147,contact members 143 and 149- bridged by the contact segment 15lconductor152, contact members 153 and l54-bridged by the contact segmentl55-conductor 156, the actuating coil of the switch 39, conductors 157and 141, the contact segment 139 of the limit switch 23 and conductor136, to the energized conductor 53.

The motor 16 is, therefore, connected to the power source through acircuit which extends from the energized conductor 53, through thearmature of the motor 16, the field winding 21, conductor 158, thecontact members of switch 39, conductors 159 and 131, the coil of therelay 43 and conductor 132, to the energized conductor 52. When the gate10 is raised to its uppermost position, the motor 16 is stopped by theopening of the limit switch 23, which interrupts the circuit through theactuating coil of the switch 39.

It is believed to be unnecessary to describe the operation of the systemin detail when a train approaches the crossing on track 2, as the trackrelay 35 functions in the same manner as the relay 34 to automaticallycontrol the apparatus to cause the gate 10 to be lowered while the trainis passing and to be raised after it has passed 130 over the insulatedsection of track 2. 7

As previously explained, the contact members of the relays 34 and 35 areso cormected in the control system that the gate 10 will be lowered whena train approaches on either one of the two tracks, and it is necessarythat both tracks be cleared before the gate 10 can be raised.

With a View to permitting the apparatus to be manually controlled tocause the gate 10 to be raised while a train is standing on one of thetracks, the manual control switches 44, 45 and 46 are provided, and maybe actuated to effect the raising of the gate 10. Assuming that a trainis standing on the insulated section of track 1 and it is desired toraise the gate 10 to clear the crossing 11, it is necessary for thebrakeman, or other authorized person, to open the control switch 44 andclose the switch 46 in order to cause the gate 10 to be raised. 150

It will be observed that opening the switch 44 will interrupt the shuntcircuit established around the actuating coil of the relay 34 through:the track 1, provided the relay 49 is actuated to establish a circuitwhich extends from the positive conductor 74, through the switch 46,conductor 161, the contact members of the relay 47, conductors 162 and163, the actuating coil of the ,relay 49 and conductor 164, to thenegative conductor 83. Therefore, by opening the switch 44 and closingthe switch 46, the actuating coil of the relay 34 is energized toactuate the relay to its uppermost position, thereby causing the gate 10to be raised, in a manner previously described.

When the switch 46 is closed, a circuit is also established through theactuating coil of the relay 47, which extends from the positiveconductor 74, through the switch 46, conductor 165, the push-buttonswitch 48, conductor 166, the coil of the relay 4'7 and conductors 167and 164, to the negative conductor 83. However, as illustrated, therelay 4'7 is a time-delay relay, and its contact members will not beopened for a predetermined time interval after the actuating coil isenergized. Therefore, the circuit through the actuating coil of therelay 49 will not be interrupted until the expiration of the period oftime for which the relay 4'7 isadjusted, and the gate 'lO'Wll]. remainraised during this time interval.

, As previously explained, the interval of time during which the gate 10is permitted to be raised, may be varied by adjusting the time settingof the relay 4'7. In case it is desired to maintain the gate 10 in theraised position for a longer period of time than that permitted by theoperation of the relay 47, the push-button switch 48 may be actuated tointerrupt the circuit through the coil of the relay 47, therebypermitting the contact members of the relay 47 to reestablish thecircuit through the actuating coil of the relay 49, which causes therelay 34 to be energized from the battery 36 to raise the gate '10, aspreviously explained. When the pushbutton switch 48 is released, theactuating coil of the relay 47 is energized, and its contact memberswill be opened, after the predetermined time interval, to cause the gate10 to be lowered and the system to be returned from manual to automaticcontrol.

In the event that a train approaches the crossing 11 on track 2 while atrain is standing on track 1 and the gate 10 has been raisedmanually, aspreviously described, the relay 35 will function in the normal manner,since the switch 45' is closed to cause the gate 10 to be lowered toprotect the crossing 11. The switch 45 and relay 51 function in the samemanner as the switch 44 and the relay 49 to provide for manually raisingthe gate 10 in the manner described for track 1 while the train isstanding on track 2.

When it is desired to return the apparatus to automatic control by therelays 34 and 35, the switch 46 is opened and the switch 44, or theswitch 45, as the case may be, is closed, thereby permitting the relays34 and 35 to function in the normal manner.

It will be understood that the possibility of any person forgetting toreturn the switches 44, 45 and 46 to the correct position for automaticcontrol and thereby leaving the crossing unprotected is precluded by theoperation of the relay 47. As previously explained, the relay 47functions to establish the automatic control at a predetermined timeinterval after the operation of the manual-control switch 46.

Although I have shown a hydraulically-operated mechanism for raising andlowering the gate 10, it will be readily understood that the controlapparatus and system herein described may be utilized for controllingrailway-crossing gates, which are operated by a mechanism of any othersuitable type, and the control apparatus is not limited to theparticular mechanism herein shown.

It will be evident from the foregoing description that I have provided acontrol system for automatically controlling the gates of a railwaycrossing which is safe and reliable in operation and is suitable for useon a railway system having a plurality of tracks. I have also providedfor manually controlling the crossing gates when it is desired to do sobut have precluded the possibility of any person leaving the crossingunprotected by the automatic control system.

It will also be readily understood that the system of my invention isnot only suitable for controlling the operation of crossing gates of thetype illustrated, but may also be used to control crossing protectivedevices of all kinds which are operable to close the crossing againsttrafiic.

Since many modifications may be made in the apparatus and arrangement ofparts without departing from the spirit of my invention, I do not wishto be limited other than by the scope of the appended claims.

I claim as my invention: 1

1. In a control system for railway-crossing gates, in combination, agate disposed to be actuated to guard a railway crossing, means foractuating the gate, switching means for con trolling the gate-actuatingmeans, means for transferring the gate-actuating means from one powersource to another in case of failure of one power source, and arelayhaving an actuating coil connected to a section of the railwaytrack and contact members disposed to control the switching means tocause the gate to be actuated to guard the crossing While a train ispassing.

2. In a control system for railway-crossing gates, in combination, agate disposed to be raised and lowered, means for raising and loweringthe gate, a plurality of motors for operating the gate-actuating means,switching means for controlling the mctors, means for transferring themotor connections from one power source to another in case of failure ofone power source, and

.a relay responsive to the approach of a train for controlling theswitching means to cause the gate to be lowered while the train isapproaching and passing the crossing and raised after it has passed thecrossing.

3. In a control system for railway-crossing gates, in combination, agate disposed to be raised and lowered, means for actuating the gate,reversible motors for operating the gate-actuating-means, switchingmeans for controlling the direction of rotation of the motors, means fortransferring the motor connections from one power source to another incase of failure of one power source, and a relay connected to a sectionof the railway track and disposed to be actuated when a train is on thetrack section for controlling the switching means to cause the gate tobe lowered while the train is passing and raised after it has passed thecrossing.

4. In a control system for railway-crossing gates, in combination, agate disposed to be raised and lowered, means for actuating the gate, aplurality of motors for driving the gate-actuating means, independentsources of power for the motors, a relay for transferring the motorconnections from one power source to the other in case of failure of theone source, switching means for reversing the motors to control themovement of the gate, and a track relay disposed to control theswitching means to cause the gate to be lowered while a train is passingand raised after it has passed the crossing.

5. In a control system for railway-crossing gates, in combination, agate disposed to be raised and lowered, means for actuating the gate, aplurality of motors for driving the gate-actuating means, independentsources of power for operating the motors, switching means forconnecting the motors to the power sources and for controlling thedirection of rotation of the motors, a relay for transferring the motorconnections from one source of power to another in case of failure ofthe one source, and a track relay disposed to be actuated when a trainapproaches the crossing for controlling the switching means to cause thegate to be lowered while the train is passing and raised after it haspassed the crossing.

6. In a control system for railway-crossing gates, in combination, agate disposed to be raised and lowered, means for actuating the gate, analternating-current motor and a direct-current motor disposed to drivethe gate-actuating means, a source of alternating-current power, asource of direct-current power, switching means for connecting themotors to the power sources and for controlling the direction ofrotation of the motors, a relay for transferring the motor connectionsfrom the alternating-current source of power to the direct-currentsource of power in case of failure of the alternating-current power, anda track relay disposed to be actuated when a train approaches thecrossing for controlling the switching means to cause the gate to belowcred while the train is passing and raised after it has passed thecrossing.

'7. In a control system for railway-crossing gates, in combination, agate disposed to be actuated to guard the crossing, means for actuatingthe gate, a plurality of motors for driving the gate-actuating means,independent sources of power for the motors, switching means forcontrolling the motors, a track relay disposed to be actuated when atrain approaches the crossing to cause the gate to be actuated to guardthe crossing while the train is passing, and switching means disposed torender the track relay ineffective, thereby permitting the gate to bemanually controlled.

8. In a control system for railway-crossing gates, in combination, agate disposed to be actuated to guard the crossing, means for actuatingthe gate, a plurality of motors for driving the gate-actuating means,independent sources of power for the motors, switching means forcontrolling the motors, a track relay disposed to be actuated when atrain approaches the crossing to cause the gate to be actuated to guardthe crossing while the train is passing, switching means disposed torender the track relay ineffective to permit the gate to be manuallycontrolled, and means for limiting the time during which the gate may bemanually controlled.

9. In a control system for railway-crossing gates, in combination, agate disposed to be raised and lowered, means for actuating the gate, aplurality of motors for driving the gate-actuating means, independentsources of power for operating the motors, switching means forconnecting the motors to the power sources, means for controlling saidswitching means to deenergize one motor and energize another motor incase of an overload on the first or" said motors, and relay meansdisposed to be actuated when a train approaches the crossing forcontrolling the switching means to cause the gate to be lowered whilethe train is passing and raised after it has passed the crossing.

10. In a control system for railway-crossing 110 gates, in combination,a gate disposed to be raised and lowered, means for actuating the gate,an alternating-current motor and a direct-current motor disposed todrive the gate-actuating means, a source of alternating current power, asource of direct-current power, switching means for connecting themotors to their respective power source, relay means for controllingsaid switching means to disconnect the alternating-current motor fromits power source and to connect the direct-current motor to thedirectcurrent power source in case of an overload. on thealternating-current motor, and relay means for controlling the switchingmeans to cause the gate to be lowered while a train is passing and 125raised after it has passed the crossing.

WALDEMAR I. BENDZ.

